Contact switch



NOV. 4,1947. 5, DIOUCETTE 2,430,215

CONTACT SWITCH Filed April 25, 1945 Edna/20 Davey/f5 I INVENTOR 7 ATTORNEY Patented Nov. 4, 1947 CONTACT SWITCH Edmund Doucette, Newark, N. J., assignor to The Daven Company, Newark, N. J., a corporation of New Jersey Application April 25, 1945, Serial No. 590,267

9 Claims. (Cl. 200-11) This invention relates to an electrical switch, and more particularly to a switch for use in decade resistors, attenuators, or similar instruments where the switch contacts sweep over aplurality of stationary contacts.

An object of the present invention is to provide an electrical switch wherein the contact members are yieldably carried by the movable carrying body of the switch for yielding movement relative thereto to provide a firm, positive contact at all times with the stationary contacts with which they co-operate, irrespective of wear or unevenness of the mounting of the stationary contacts.

A further object of the present invention is to provide a switch as specified which is simple in construction, embodying a minimum number of parts and which is so constructed and arranged as to prevent accidental displacement of parts during use.

The switch of the present invention is particularly adapted for use in attenuators as disclosed in my companion application Serial No. 590,266 filed April 25, 1945, and that shown in my copending application Serial No. 579,829, filed February 26, 1945.

With these and other objects in view, as may appear from the accompanying specification, the invention consists of various features of construction and combination of parts, which will be first described in connection with the accompanying drawings, showing a contact switch of a preferred form embodying the invention, and the features forming the invention will be specifically pointed out in the claims.

In the drawings:

Figure 1 is a side'elevation of the improved switch showing it in operative position on the contact end of an attenuator or like instrument.

Figure 2 is a side elevation of the improved switch showing the inner side or that opposite to the side shown in Figure 1.

Figure 3 is a section through the switch taken on the line 3-3 of Figure 1.

Figure 4 is an enlarged fragmentary section of the switch taken on part of the line 3-3 of Figure 1.

Referring more particularly to the drawings, an attenuator or similar electrical instrument is indicated at I which has an outer circle of spaced stationary contacts 2 and an inner ring contact 3, the bridging of which permits the flow of electrical current, and the position of the switch member establishing contact between certain of the spaced stationary contacts 2, and the rin 3 determines and regulates the degree of resistance imposed upon the flow of the electrical current.

The attenuator I, or like instrument, embodies a shaft 4 upon which the improved switch structure 5 is mounted.

The switch structure 5 includes the carrying body 6 which is constructed of suitable insulating material and has a'substantially semi-circular inner end 1 which carries a bearing sleeve 8 bored to receive the shaft 4 for mounting the switch structure upon the end of the shaft. Suitable means generically indicated at 9 is provided for locking the switch 5 upon the shaft 4. This locking mechanism forms the subject matter of my companion application Serial No. 590,266 filed April 25, 1945, and, consequently, will not be described and claimed herein; The edges of the carrying body 5 incline towards each other as they extend from the semi-circular mounting end 1 towards the outer free end of the body. I

The carrying body 6 is provided with a pair of parallel spaced openings [0 and H near its outer free end. A pair of inverted U-shaped contact members 12 and I3 are provided, and one of the parallel legs of each of these U-shaped members extends through each of the parallel openings l0 and II with the inverted U-shaped contact member l3 being nested within the inverted U-shaped contact member l2, as clearly shown in Figures 3 and 4 of the drawings. The ends of the legs of the U-shaped members extend through the body 6 of the carrying member 5 and. are positioned so that the protruding contact ends next to the axis of rotation of the carryin body 5 will engage the inner contact ring 3, while the protruding ends of the legs furthest from the pivotal axis of the switch will engage and sweep over the spaced contacts of the outer ring of contacts 2, thus establishing through the inverted U-shaped members electrical connection between the inner contact ring 3 and the contacts in the outer ring 2. The inverted U-shaped contact members l2 and I3 may move in the openings l0 and II, and they are steadied in their connection with the carrying body 6, and are urged towards the carrying body so that their contact ends will be yieldably held in engagement with the respective contacts of the instrument I by flat spring members l4 and I 5.

The flat spring plates l4 and I5 are placed one above the other, as clearly shown in Figure 4 of the drawings, and they are riveted, or otherwise suitably fastened, to the carrying body 6 at their inner ends, and, as shown at I 6, leaving their outer ends free. The outer end of the spring plate M contacts the connecting bar of the inverted U-shaped contact member l2, while the outer free end of the plate spring l5 engages the connecting bar of the inner inverted U-shaped contact member I 3, thus independently urging the two inverted U-shaped contact members into contact with the stationary contacts of the instrument I. The spring plates [4 and [5 are provided with cut-out portions l1 so as to prevent the interference of one with the other in the holding of the respective inverted U-shaped contact members so as to permit free, unimpeded yieldable movement of each inverted U-shaped contact member relative to the other.

The inverted U-shaped contact members are positioned at an acute angle to the radii of the concentric circles of the contacts 2 and 3, as clearly shown in Figure l of the drawings, so that during rotation of the switch member, the ends of the protruding contact-engaging portions of the inverted U-shaped members will sweep over the entire contact surface of the space contacts 2 and the inner contact ring 3 for the purpose of keeping even wear on these contact surfaces and sweeping them clean of any foreign material which might tend to settle thereon t will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown, but that they may be widely modified within the invention defined by the claims.

What is claimed is:

1. In an electrical switch, a movable contact carrying body, said contact carrying body pro vided with a pair of spaced openings therein, a pair of inverted U-shaped contact members carried by said body and having their legs inserted through said openings, and means engaging said contact members for urging them in contact engaging position.

2. In an electrical switch, a movable contact carrying body, said contact carrying body provided with a pair of spaced openings therein, a pair of inverted U-shaped contact members carried by said body and havin their legs inserted through said openings and flat springs carried by said body and engaging said inverted U-shaped contact members for urging them in contactengaging positions.

3. In an electrical switch, a movable contactcarrying body, said contact carrying body provided with a pair of spaced openings therein, a pair of inverted U-shaped contact members carried by said body and having their legs inserted through said openings, .said inverted U-shaped contact members being nested one within the other, and springs carried by said body and one each engaging one of said inverted U-shaped members for urging the inverted U-shaped members into stationary contact-engaging positions.

In an electrical switch, a movable contactcarrying body, said contact-carrying body provided with a pair of spaced openings therein, a pair of inverted U-shaped contact members carried by said body and having their legs inserted through said openings, said inverted U-shaped contact members being nested one within the other, a pair of flat springs carried by said body and one each engaging one of said inverted U- shaped members for urging the inverted U -shaped members into stationary contact-engaging posi tions, and the fiat spring which engages the inner inverted U-shaped member being provided with an opening to receive therethrough one leg of the outer inverted U-shaped member to permit independent unimpeded movement of the outer inverted U -shaped member.

5. In an electrical switch, a movable contactcarrying body provided with a pair of spaced openings extending therethrough, an inverted U- shaped contact member having its legs inserted through said openings to permit movement of the inverted U-shaped contact member relative to the carrying body, and a spring engaging said inverted U-shaped contact member to yieldably support it in position relative to the contact-carrying body.

6. In an electrical switch, a contact carrying body movable about a fixed aXls, said body provided with a pair of spaced openings therein, an inverted U-shaped contact member having its legs inserted through said openings to permit movement of the inverted U-shaped contact member relative to the carrying body, spring engaging said inverted U-shaped contact member to yieldably support it in position relative to the contact carrying body, the legs of said U-shaped contact member being disposed relative to the radii of a circle formed by movement of said carrying body on its fixed axis so that the legs are skewed to move obliquely of the circle.

7. In an electrical switch, a contact carrying body movable about a fixed axis and provided with a pair of spaced openings therein, a pair of inverted U-shaped contact carrying members carried by said body and having their legs inserted through said openings, means engaging said contact members for urging them in contact engaging position, said legs being skewed relative to the radius of a circle concentric oi the fixed axis of the carrying body and bisecting the legs so that the legs will move obliquely across the perimeter of such a circle.

8. In an electrical switch, a contact carrying body movable about a fixed axis and provided with a pair of spaced openings therein, a pair of inverted U-shaped members carried by said body and having their legs inserted through said openings, said inverted U-shaped members nested one within the other, a fiat spring having one end attached to said carrying body, and its other end engaging the outermost of said nested inverted U-shaped members, a second fiat spring having one end attached to said carrying body and its other end engaging the innermost of said nested inverted U-shaped members, said second spring provided with an opening to receiv therethroiigh one leg of said outermost inverted U-shaped member.

9. In an electrical switch, a contact carrying body movable about a fixed axis and provided with a pair of spaced openings therein, a pair of inverted U-shaped members carried by said body and having their legs inserted through said openings, said inverted U-shaped members nested one within the other, a fiat spring having one end attached to said carrying body, and its other end engaging the outermost of said nested inverted U-shaped members, a second fiat spring having one end attached to said carrying body and its other end engaging the innermost of said nested inverted U-shaped members, said second spring provided with an opening to receive therethrough one leg of said outermost inverted U-shaped member, said legs being skewed relative to the radius of a circle concentric of the fixed axis of the carrying body and bisecting the legs so that the legs will move obliquely across the perimeter of such a circle.

EDMUND DOUCETTE.

REFERENCES CITED UNITED STATES PATENTS Name Date Ross May 25, 1937 Number 

